Subject Re: NULL Date values
Author jeff_j_dunlap
--- In, "Adam" <s3057043@...> wrote:
> What is the confusion?
> Nov 17 1858 is day 0.
> Nov 16 1858 is day -1
> Nov 15 1858 is day -2
> etc.
> The data definition simply tells you not to try and use dates
> that range.
> As Ann (and others have advised), if the *null flag* is set on a
> field, the *value* stored in that field is not relevant. An
> implementation artifact causes the *value* to be set to 0 when the
> field is null.
> Zero and null are 2 different things. If you don't understand that,
> you should read the Firebird Null Guide on this page:
> Older versions of Firebird were not able to pass a null to a UDF, so
> it is understandable that such UDFs would use the value stored in
> field ignoring the null flag. Firebird 2 supports null signals to
> calls. (See chapter 13 of release notes).
> So if you want your UDFs to handle NULL properly, you will need to
> using Firebird 2, using a version of the UDF that understands the
> convention (check with UDF vendor), and have the UDF declared in
> database to correct way (check with UDF vendor).
> Adam


Thanks for your makes alot more sense to me now.

Best Regards,